Nutrient removal from wastewaters using high performance materials

Return side streams from anaerobic digesters and dewatering facilities at wastewater treatment plants (WWTPs) contribute a significant proportion of the total nitrogen load on a mainstream process. Similarly, significant phosphate loads are also recirculated in biological nutrient removal (BNR) wastewater treatment plants. Ion exchange using a new material, known by the name MesoLite, shows strong potential for the removal of ammonia from these side streams and an opportunity to concurrently reduce phosphate levels. A pilot plant was designed and operated for several months on an ammonia rich centrate from a dewatering centrifuge at the Oxley Creek WWTP, Brisbane, Australia. The system operated with a detention time in the order of one hour and was operated for between 12 and 24 hours prior to regeneration with a sodium rich solution. The same pilot plant was used to demonstrate removal of phosphate from an abattoir wastewater stream at similar flow rates. Using MesoLite materials, >90% reduction of ammonia was achieved in the centrate side stream. A full-scale process would reduce the total nitrogen load at the Oxley Creek WWTP by at least 18%. This reduction in nitrogen load consequently improves the TKN/COD ratio of the influent and enhances the nitrogen removal performance of the biological nutrient removal process.

Effects of whole body cryotherapy and cold water immersion on knee skin temperature

This study sought to a) compare and contrast the effect of 2 commonly used cryotherapy treatments, 4 min of − 110 °C whole body cryotherapy and 8 °C cold water immersion, on knee skin temperature and b) establish whether either protocol was capable of achieving a skin temperature ( < 13 °C) believed to be required for analgesic purposes. After ethics committee approval and written informed consent was obtained, 10 healthy males (26.5 ± 4.9 yr, 183.5 ± 6.0 cm, 90.7 ± 19.9 kg, 26.8 ± 5.0 kg/m 2 , 23.0 ± 9.3 % body fat; mean ± SD) participated in this randomised controlled crossover study. Skin temperature around the patellar region was assessed in both knees via non-contact, infrared thermal imaging and recorded pre-, immediately post-treatment and every 10 min thereafter for 60 min. Compared to baseline, average, minimum and maximum skin temperatures were significantly reduced (p < 0.001) immediately post-treatment and at 10, 20, 30, 40, 50 and 60 min after both cooling modalities. Average and minimum skin temperatures were lower (p < 0.05) immediately after whole body cryotherapy (19.0 ± 0.9 ° C) compared to cold water immersion (20.5 ± 0.6 ° C). However, from 10 to 60 min post, the average, minimum and maximum skin temperatures were lower (p < 0.05) following the cold water treatment. Finally, neither protocol achieved a skin temperature believed to be required to elicit an analgesic effect.

Application of kaolin amorphous derivative as a nitrogen carrier

Sandy soils have low nutrient holding capacity and high water conductivity. Consequently, nutrients applied as highly soluble chemical fertilisers are prone to leaching, particularly in heavily irrigated environments such as horticultural soils and golf courses. Amorphous derivatives of kaolin with high cation exchange capacity may be loaded with desired nutrients and applied as controlledrelease fertilisers. Kaolin is an abundant mineral, which can be converted to a meso-porous amorphous derivative (KAD) using facile chemical processes. KAD is currently being used to sequester ammonium from digester effluent in sewage treatment plants in a commercial environment. This material is also known in Australia by the trade name MesoLite. The ammonium-saturated form of KAD may be applied to soils as a nitrogen fertiliser. Up to 7% N can be loaded onto KAD by contacting it with high-ammonia concentration wastewater from sewerage treatment plants. This poster paper demonstrates plant uptake of nitrogen from KAD and compares its efficiency as a fertiliser with NH4SO4. Rye grass was grown in 1kg pots in a glass-house. Nitrogen was applied at a range of rates using NH4SO4 and two KAD materials carrying 7% and 3% nitrogen, respectively. All other nutrients were applied in adequate amounts. All treatments were replicated three times. Plants were harvested after four weeks. Dry mass and N concentrations were determined by standard methods. At all N application rates, ammonium-loaded KAD produced significantly higher plant mass than for NH4SO4. The lower fertiliser effectiveness of NH4SO4 is attributed to possible loss of some N through volatilisation. Of the two KAD types, the material with lower CEC value supported slightly higher plant yields. The KAD materials did not show any adverse effect on availability of trace elements, as evidenced by lack of deficiency symptoms and plant analyses. Clearly, nitrogen loaded on to KAD in the form of ammonium is likely to be protected from leaching, but is still available to plants. These data suggest that KAD-based fertilisers may be suitable substitutes for water soluble N, K and other cation fertilisers for leaching soils.

Synthesis, characterisation and application of organic surfactants modified clays for water purification

This thesis offered a step forward in the development of cheap and effective materials for water treatment. It described the modification of naturally abundant clay minerals with organic molecules, and used the modified clays as effective adsorbents for the removal of recalcitrant organic water pollutants. The outcome of the study greatly extended our understanding of the synthesis and characteristic properties of clay and modified clay minerals, provided optimistic evaluation of the modified clays for environmental remediation and offered potential utility for clay minerals in the industry and environment.

New catalysts for organic synthesis driven by light and efficient sorbents for removal of radioactive ions from water

The body of the thesis contained two separate elements which made an original contribution to fundamental understanding in the areas of photocatalysis, chemical synthesis and water treatment. Research on chemical reactions catalyzed by noble metal nanoparticles (such as gold) or surface complex grafted metal oxides which can be driven by sunlight at ambient temperature and the second element on radioactive cesium (137Cs+) cations and iodine (125I-) anions recovery by the unique structural features of titanate nanostructures for firmly capture and safe storage; the works has been all published in journals that are rated at the top of their respective fields.

First aid treatment of burn injuries

The recommendations for the first aid treatment of burn injuries have previously been based upon conflicting published studies and as a result the recommendations have been vague with respect to optimal first aid treatment modality, temperature, duration and delay after which treatment is still effective. The public have also continued to use treatments such as ice and alternative therapies, however there is little evidence to support their use. Recently there have been several studies conducted by burn researchers in Australia which have enabled the recommendations to be clarified. First aid should consist of cool running water (2-15°C), applied for 20 minutes duration, as soon as possible but for up to 3 hours after the burn injury has occurred. Ice should not be used and alternative therapies should only be used to relieve pain as an adjunct to cold water treatment. Optimal first aid treatment significantly reduces tissue damage, hastens wound re-epithelialisation and reduces scarring and should be promoted widely to the public.

Pilot plant studies of ion exchange for desalination of coal seam gas produced water

This paper reports a study of ion exchange (IX) as an alternative CSG water treatment to the widely used reverse osmosis (RO) desalination process. An IX pilot plant facility has been constructed and operated using both synthetic and real CSG water samples. Application of appropriate synthetic resin technology has proved the effectiveness of IX processes.

Carbon nanotube membranes with ultrahigh specific adsorption capacity for water desalination and purification

Development of technologies for water desalination and purification is critical to meet the global challenges of insufficient water supply and inadequate sanitation, especially for point-of-use applications. Conventional desalination methods are energy and operationally intensive, whereas adsorption-based techniques are simple and easy to use for point-of-use water purification, yet their capacity to remove salts is limited. Here we report that plasma-modified ultralong carbon nanotubes exhibit ultrahigh specific adsorption capacity for salt (exceeding 400% by weight) that is two orders of magnitude higher than that found in the current state-of-the-art activated carbon-based water treatment systems. We exploit this adsorption capacity in ultralong carbon nanotube-based membranes that can remove salt, as well as organic and metal contaminants. These ultralong carbon nanotube-based membranes may lead to next-generation rechargeable, point-of-use potable water purification appliances with superior desalination, disinfection and filtration properties. © 2013 Macmillan Publishers Limited.

Chemical and bioanalytical assessment of coal seam gas associated water

A comprehensive study was undertaken involving chemical (inorganic and organic) and bioanalytical (a suite of 14 in vitro bioassays) assessments of coal seam gas (coal bed methane) associated water (CSGW) in Queensland, Australia. CSGW is a by-product of the gas extraction process and is generally considered as water of poor quality. This was done to better understand what is known about the potential biological and environmental effects associated with the organic constituents of CSGW in Australia. In Queensland, large amounts of associated water must be withdrawn from coal seams to allow extraction of the gas. CSGW is disposed of via release to surface water, reinjected to groundwater or reused for irrigation of crops or pasture, supplied for power station cooling and or reinjected specifically to augment drinking water aquifers. Groundwater samples were collected from private wells tapping into the Walloon Coal Measures, the same coal aquifer exploited for coal seam gas production in the Surat Basin, Australia. The inorganic characteristics of these water samples were almost identical to the CSGW entering the nearby gas company operated Talinga-Condabri Water Treatment Facility. The water is brackish with a pH of 8 to 9, high sodium, bicarbonate and chloride concentrations but low calcium, magnesium and negligible sulphate concentrations. Only low levels of polyaromatic hydrocarbons (PAHs) were detected in the water samples, and neither phenols nor volatile organic compounds were found. Results from the bioassays showed no genotoxicity, protein damage, or activation of hormone receptors (with the exception of the estrogen receptor). However, five of the 14 bioassays gave positive responses: an arylhydrocarbon-receptor gene activation assay (AhR-CAFLUX), estrogenic endocrine activity (ERα-CALUX), oxidative stress response (AREc32), interference with cytokine production (THP1-CPA) and non-specific toxicity (Microtox). The observed effects were benchmarked against known water sources and were similar to secondary treated wastewater effluent, stormwater and surface water. As mixture toxicity modelling demonstrated, the detected PAHs explained less than 5% of the observed biological effects.

Leptospirosis from water sources

Leptospirosis outbreaks have been associated with many common water events including water consumption, water sports, environmental disasters and occupational exposure. The ability of leptospires to survive in moist environments makes them a high risk agent for infection following contact with any contaminated water source. Water treatment processes reduce the likelihood of leptospirosis or other microbial agents causing infection provided they do not malfunction and the distribution networks are maintained. Notably, there are many differences in water treatment systems around the world, particularly between developing and developed countries. Detection of leptospirosis in water samples is uncommonly performed by molecular methods.

Ion exchange treatment of saline solutions using lanxess S108H strong acid cation resin

Common to many types of water and wastewater is the presence of sodium ions which can be removed by desalination technologies, such as reverse osmosis and ion exchange. The focus of this investigation was ion exchange as it potentially offered several advantages compared to competing methods. The equilibrium and column behaviour of a strong acid cation (SAC) resin was examined for the removal of sodium ions from aqueous sodium chloride solutions of varying normality as well as a coal seam gas water sample. The influence of the bottle-point method to generate the sorption isotherms was evaluated and data interpreted with the Langmuir Vageler, Competitive Langmuir, Freundlich, and Dubinin-Astakhov models. With the constant concentration bottle point method, the predicted maximum exchange levels of sodium ions on the resin ranged from 61.7 to 67.5 g Na/kg resin. The general trend was that the lower the initial concentration of sodium ions in the solution, the lower the maximum capacity of the resin for sodium ions. In contrast, the constant mass bottle point method was found to be problematic in that the isotherm profiles may not be complete, if experimental parameters were not chosen carefully. Column studies supported the observations of the equilibrium studies, with maximum sodium loading of ca. 62.9 g Na/kg resin measured, which was in excellent agreement with the predictions of the data from the constant concentration bottle point method. Equilibria involving coal seam gas water were more complex due to the presence of sodium bicarbonate in solution, albeit the maximum loading capacity for sodium ions was in agreement with the results from the more simple sodium chloride solutions.

Degradability of creatinine under sewer conditions affects its potential to be used as biomarker in sewage epidemiology

Creatinine was proposed to be used as a population normalising factor in sewage epidemiology but its stability in the sewer system has not been assessed. This study thus aimed to evaluate the fate of creatinine under different sewer conditions using laboratory sewer reactors. The results showed that while creatinine was stable in wastewater only, it degraded quickly in reactors with the presence of sewer biofilms. The degradation followed first order kinetics with significantly higher rate in rising main condition than in gravity sewer condition. Additionally, daily loads of creatinine were determined in wastewater samples collected on Census day from 10 wastewater treatment plants around Australia. The measured loads of creatinine from those samples were much lower than expected and did not correlate with the populations across the sampled treatment plants. The results suggested that creatinine may not be a suitable biomarker for population normalisation purpose in sewage epidemiology, especially in sewer catchment with high percentage of rising mains.

Brief for GSDR - Emerging Contaminants in urban stormwater: Challenges and perspectives for sustainable water use

Emerging contaminants (ECs) are chemical compounds commonly present in water. It is only recently that this family of compounds is being recognized as significant water pollutants (. ECs include a wide variety of chemicals such as pharmaceutical and personal care products (PPCPs), pesticides, hydrocarbons and hormones, among others, that once released into the environment exert adverse impacts on the human and wildlife endocrine system. Natural attenuation and conventional treatment processes are not capable of removing these micro-pollutants detected in wastewater influent and effluent and surface and drinking water. The main challenges related with presence of ECs in stormwater in the context of reuse are: a) Development of suitable laboratory test methodologies and protocols for ECs identification and quantification b) Identification of the sources of ECs in the urban environment; c) Understanding their impacts on human and/or ecosystem health; and d). Development of cost-effective removal technologies which are appropriate for large as well as small-scale application.